cmake_minimum_required(VERSION 3.3)

project(vcpkg C CXX)

OPTION(DEFINE_DISABLE_METRICS "Option for disabling metrics" OFF)
OPTION(VCPKG_ALLOW_APPLE_CLANG "Option for allowing apple clang" OFF)

if(CMAKE_COMPILER_IS_GNUXX OR CMAKE_CXX_COMPILER_ID MATCHES "GNU")
    set(GCC 1)
elseif(CMAKE_CXX_COMPILER_ID MATCHES "AppleClang")
    if(NOT VCPKG_ALLOW_APPLE_CLANG)
        message(FATAL_ERROR
"Building the vcpkg tool requires support for the C++ Filesystem TS.
Apple clang versions 9 and below do not have support for it.
Please install gcc6 or newer from homebrew (brew install gcc6).
If you would like to try anyway, pass --allowAppleClang to bootstrap.sh.")
    else()
        set(CLANG 1)
    endif()
elseif(CMAKE_CXX_COMPILER_ID MATCHES "[Cc]lang")
    set(CLANG 1)
elseif(MSVC)
    add_compile_options(/std:c++17)
else()
    message(FATAL_ERROR "Unknown compiler: ${CMAKE_CXX_COMPILER_ID}")
endif()

if(GCC OR CLANG)
    add_compile_options(-std=c++1z)
    if(WERROR)
        add_compile_options(-Wall -Wno-unknown-pragmas -Werror)
    endif()
endif()

file(GLOB_RECURSE VCPKGLIB_SOURCES src/vcpkg/*.cpp)

if (DEFINE_DISABLE_METRICS)
    set(DISABLE_METRICS_VALUE "1")
else()
    set(DISABLE_METRICS_VALUE "0")
endif()

add_executable(vcpkg src/vcpkg.cpp ${VCPKGLIB_SOURCES})
target_compile_definitions(vcpkg PRIVATE -DDISABLE_METRICS=${DISABLE_METRICS_VALUE})
target_include_directories(vcpkg PRIVATE include)

if(CLANG)
    include(CheckCXXSourceCompiles)
    check_cxx_source_compiles("#include <iostream>
                               int main() { return __GLIBCXX__; }" USES_LIBSTDCXX)
    check_cxx_source_compiles("#include <iostream>
                               int main() { return _LIBCPP_VERSION; }" USES_LIBCXX)
    if ( NOT USES_LIBSTDCXX AND NOT USES_LIBCXX )
        message(FATAL_ERROR "Can't find which C++ runtime is in use")
    endif()
endif()

if(GCC OR (CLANG AND USES_LIBSTDCXX))
    target_link_libraries(vcpkg PRIVATE stdc++fs)
elseif(CLANG)
    target_link_libraries(vcpkg PRIVATE c++experimental)
endif()

if(MSVC)
  get_target_property(_srcs vcpkg SOURCES)

  if(NOT CMAKE_GENERATOR MATCHES "Visual Studio .*")
    set_property(SOURCE src/pch.cpp APPEND PROPERTY OBJECT_OUTPUTS "${CMAKE_CURRENT_BINARY_DIR}/pch.pch")
    set_property(SOURCE ${_srcs} APPEND PROPERTY OBJECT_DEPENDS "${CMAKE_CURRENT_BINARY_DIR}/pch.pch")
  endif()

  set_source_files_properties(src/pch.cpp PROPERTIES COMPILE_FLAGS "/Ycpch.h")
  target_sources(vcpkg PRIVATE src/pch.cpp)
  target_compile_options(vcpkg PRIVATE /Yupch.h /FIpch.h /Zm200)
endif()

set(THREADS_PREFER_PTHREAD_FLAG ON)
find_package(Threads REQUIRED)
target_link_libraries(vcpkg PRIVATE Threads::Threads)